And my counter-theory for Thanos and the IG in the MCU: Thanos has been after the Gauntlet in Odin's Treasury all along. He merely manipulated Loki (Loki didn't realize it at the time) into a failed battle for Earth, which resulted in the Cube being returned to Asgard. With the Cube in Asgard, Thanos now has the "in" to Odin's Treasury that he was after all along....i.e., he used the attack on Earth as just a ruse. He wanted Loki to lose, so that the Cube would be returned to Asgard to open up that cosmic avenue into the Treasury.

It's either that or Loki uses the Gauntlet as a means to bargain for his life.